package srting;
/*
StringBuilder修改字符串的性能
 */

public class StringBuilderDemo2 {

    public static void main(String[] args) {
        StringBuilder builder=new StringBuilder("a");
        for (int i=0;i<100000000;i++){
            builder.append("a");
        }
        System.out.println("程序结束了");






    }
}
